Absorbent sheet for pets

ABSTRACT

It is possible to provide an absorbent sheet for pets capable of making a trace of excreta of a pet difficult to be visually recognized. The absorbent sheet for pets comprising: a liquid-permeable top sheet; a liquid-impermeable back sheet; an absorbent core provided between the top sheet and the back sheet; a colored area covered with the top sheet and visually recognizable from the top sheet side; and an aroma chemical provided on the top sheet side relative to the absorbent core. L*value of the colored area in an L*a*b*color system is 50 or less. A total light transmittance of the top sheet is in a range of 40 to 80%.

TECHNICAL FIELD

The present invention relates to an absorbent sheet for pets thatabsorbs excreta, that is, urine of a pet.

BACKGROUND ART

There is a known absorbent sheet for pets that absorbs excreta, that is,urine of a pet. JP 2006-238745 A (hereinafter referred to as PatentLiterature 1) discloses an excreta absorbent sheet for pets capable ofexhibiting fragrance effect, deodorant effect, and bactericidal effect.The excreta absorbent sheet for pets disclosed in Patent Literature 1includes a liquid-impermeable back sheet, a liquid-permeable top sheet,and an absorber positioned between the back sheet and the top sheet. Inthis absorbent sheet for pets, a chemical liquid containing at least oneof a perfume component, a deodorant component, and a bactericidalcomponent is attached to the top sheet.

CITATION LIST Patent Literature

Patent Literature 1: JP 2006-238745 A

SUMMARY

When a pet excretes excreta on an excreta absorbent sheet for pets once,a trace of the excreta is let on the excreta absorbent sheet for pets.Therefore, even when an odor resulting from the trace of the excreta isremoved, a user feels unsanitary by visually recognizing the trace ofthe excreta. Therefore, even when the deodorant effect is maintained,the user may attempt to replace the excreta absorbent sheet for pets.

The invention has been conceived in view of the above-mentioned problem,and an object of the invention is to provide an absorbent sheet for petscapable of making a trace of excreta of a pet difficult to be visuallyrecognized.

An absorbent sheet for pets according to the present disclosure includesa liquid-permeable top sheet, a liquid-impermeable back sheet, anabsorbent core provided between the top sheet and the back sheet, acolored area covered with the top sheet and recognizable from a topsheet side, and an aroma chemical provided on a top sheet side relativeto the absorbent core. An L*value of the colored area in an L*a*b*colorsystem is 50 or less. A total light transmittance of the top sheet is ina range of 40 to 80%.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view of an absorbent sheet for pets according to afirst embodiment.

FIG. 2 is a cross-sectional view of the absorbent sheet for pets takenalong A-A line illustrated in FIG. 1.

FIG. 3 is a cross-sectional view of an absorbent sheet for petsaccording to a second embodiment.

FIG. 4 is a cross-sectional view of an absorbent sheet for petsaccording to a third embodiment.

DESCRIPTION OF EMBODIMENTS

Hereinafter, an absorbent sheet for pets according to embodiments willbe described with reference to drawings. In description of the drawingsbelow, the same or similar reference numeral will be assigned to thesame or similar portion. However, the drawings are schematic, and itshould be noted that a ratio of respective dimensions, etc. is differentfrom an actual one. Therefore, specific dimensions, etc. need to bedetermined by taking the description below into consideration. Inaddition, a portion in which a relation or a ratio of dimensions isdifferent between drawings may be included.

In this specification, “pets” widely include a vertebrate and aninvertebrate, and typically include a pet such as a cat, a dog, arabbit, a hamster, etc.

(1) Configuration of Absorbent Sheet for Pets

FIG. 1 is a plan view of an absorbent sheet for pets. FIG. 2 is across-sectional view of the absorbent sheet for pets taken along A-Aline illustrated in FIG. 1. An absorbent sheet for pets 10 is a flatsheet. One surface of the sheet is a surface receiving excreta, and willbe also referred to as an “excretion surface”. FIG. 1 is a plan view ofan absorbent sheet for pets viewed from an excretion surface side.

The absorbent sheet for pets 10 includes a top sheet 12, a back sheet14, and an absorbent core 20. The absorbent core 20 is provided betweenthe top sheet 12 and the back sheet 14.

The top sheet 12 is a liquid-permeable sheet that allows a liquid suchas excreta of a pet to permeate the sheet. For example, air-throughnonwoven fabric may be used as the top sheet 12. However, the top sheet12 is not particularly restricted. The back sheet 14 is aliquid-impermeable sheet into which a liquid such as excreta of the petdoes not permeate. For example, a resin film sheet may be used as theback sheet 14. However, the back sheet 14 is not particularlyrestricted.

The absorbent core 20 includes a pulp and an absorbent material.Examples of the absorbent material include a hydrophilic fiber, a superabsorbent polymer, or a combination thereof. The absorbent core 20 has awater-holding capacity of 1,000 g/m² or more, preferably 2,000 g/m² ormore, and the amount of water seeping from the absorbent core 20 havingabsorbed 40 mL of water after three minutes is 10 g or less, preferably5 g or less.

The absorbent core 20 may be wound around core wrap 16. For example, thecore wrap 16 may be formed from tissue. At least one cover layer 40 maybe provided between the top sheet 12 and the absorbent core 20. Thecover layer 40 may be formed from tissue or SMS nonwoven fabric.

In an embodiment illustrated in FIG. 2, one cover layer 40 isillustrated. When the cover layer 40 is formed from tissue, the coverlayer 40 warps around the absorbent core 20 together with the core wrap16.

The super absorbent polymer 34 may be provided on the top sheet 12 siderelative to the absorbent core 20. Preferably, this super absorbentpolymer 34 is provided between the absorbent core 20 and the top sheet12. More preferably, the super absorbent polymer 34 is provided betweenthe absorbent core 20 and the cover layer 40.

Preferably, an absorption rate of the absorbent material provided in theabsorbent core 20 is higher than an absorption rate of the superabsorbent polymer 34 provided on the top sheet 12 side of the absorbentcore 20. As an example, the absorption rate of the absorbent material inthe absorbent core 20 is less than 18 seconds. In this specification,the “absorption rate” means a water absorption rate measured by a vortexmethod.

An antimicrobial and/or a bacteriostat 30 may be provided on the topsheet 12 side relative to the absorbent core 20. Preferably, theantimicrobial and/or the bacteriostat 30 is provided on the absorbentcore 20 side relative to the top sheet 12. The cover layer 40 ispreferably provided between the top sheet 12 and the antimicrobialand/or the bacteriostat 30.

Preferably, the antimicrobial and/or the bacteriostat 30 is in a powderform. More preferably, the antimicrobial and/or the bacteriostat 30 maybe formed from a powdery inorganic substance. Further, the powderyantimicrobial and/or the bacteriostat 30 may be attached to a surface ofthe super absorbent polymer 34 provided on the top sheet 12 siderelative to the absorbent core 20.

The antimicrobial may be an organic antimicrobial such as quaternaryammonium salt, p-oxybenzoic acid ester, etc. Alternatively, theantimicrobial may be an inorganic antimicrobial containing an inorganicsubstance such as Ag, Mn, Fe, Co, Ni, Cu, Zn, etc. Instead, theantimicrobial may be an antibacterial substance containing a naturalmaterial such as a tea leave, a coffee extraction residue, etc. Thebacteriostat may be a bacteriostatic substance such as organic acid,organic acid salt, etc. In addition, the antibacterial substance or thebacteriostatic substance exemplified above may be mixed with each other.

The absorbent sheet for pets 10 may include an aroma chemical 32provided on the top sheet 12 side relative to the absorbent core 20. Thearoma chemical 32 may be provided between the cover layer 40 and theabsorbent core 20.

Preferably, the aroma chemical 32 is included in cyclodextrin. Morepreferably, the cyclodextrin is solidified by a binder. Examples of thebinder include gum arabic, dextrose, glycerin, etc. A particle diameterof a particle obtained by combining the cyclodextrin and the binder ispreferably 30 μm or more.

The cyclodextrin may correspond to an arbitrary type such asα*-cyclodextrin, β-cyclodextrin, etc. The cyclodextrin included in thearoma chemical 32 may be water-soluble.

In the present embodiment, the antimicrobial and/or the bacteriostat 30and the aroma chemical 32 are provided in the same layer. The inventionis not restricted thereto, and the absorbent sheet for pets may have theantimicrobial and/or the bacteriostat 30 and the aroma chemical 32 indifferent layers. In addition, according to an embodiment, the absorbentsheet for pets may include at least one of the antimicrobial, thebacteriostat, and the aroma chemical.

FIG. 3 is a cross-sectional view of an absorbent sheet for petsaccording to a second embodiment. The same or similar reference numeralis assigned to the same or similar component as that of the firstembodiment. Similarly to the first embodiment, the absorbent sheet forpets according to the second embodiment includes a top sheet 12, a backsheet 14, an absorbent core 20, core wrap 16, the antimicrobial and/orthe bacteriostat 30, and an aroma chemical 32.

In the second embodiment, the absorbent sheet for pets includes a coverlayer 42 provided on the absorbent core 20 side relative to the topsheet 12. The cover layer 42 is disposed on an excretion surface siderelative to the core wrap 16. The cover layer 42 may be formed fromtissue or nonwoven fabric. Preferably, the cover layer 42 is formed fromSMS nonwoven fabric.

FIG. 4 is a cross-sectional view of an absorbent sheet for petsaccording to a third embodiment. The same or similar reference numeralis assigned to the same or similar component as that of the firstembodiment. Similarly to the first embodiment, the absorbent sheet forpets according to the third embodiment includes a top sheet 12, a backsheet 14, an absorbent core 20, core wrap 16, an antimicrobial and/or abacteriostat 30, and an aroma chemical 32.

In the third embodiment, in the absorbent sheet for pets, a cover layer42 and a pulp material 46 are provided between the antimicrobial and/orthe bacteriostat 30 or the aroma chemical 32 and the top sheet 12. Thecover layer 42 may be formed from tissue or nonwoven fabric. The coverlayer 42 may be disposed on an excretion surface side relative to thepulp material 46, or the pulp material 46 may be disposed on anexcretion surface side relative to the cover layer 42.

The pulp material 46 is wrapped with the core wrap 16 together with theabsorbent core 20. The pulp material 46 allows pet excreta to rapidlypermeate the pulp material 46 toward the absorbent core 20. In this way,drying of the top sheet 12 may be promoted after the pet excretesexcreta.

In the first to third embodiments, only one cover layer 40 or 42 isillustrated. Alternatively, the absorbent sheet for pets may have aplurality of cover layers.

In the first to third embodiments, the absorbent sheet for pets 10 has acolored area 18 visually recognizable from the top sheet 12 side. Thecolored area 18 may be formed on the top sheet 12. Instead, the coloredarea 18 may be formed in the cover layer 40 or 42 provided on theabsorbent core 20 side relative to the top sheet 12. Alternatively, thecolored area 18 may be formed in the absorbent core 20.

Preferably, the colored area 18 is formed on the absorbent core 20 siderelative to the top sheet 12, and the top sheet 12 covers the coloredarea 18. In this case, total light transmittance of the top sheet 12 ispreferably in a range of 40 to 80%, and an L*value of the colored area18 in an L*a*b*color system is preferably 50 or less. Here, the totallight transmittance may be measured by a test method according to JIS K7105.

The L*value of the L*a*b*color system less than or equal to 50 indicatesa so-called dark color. A dark color system absorbs a color due toliquid excreta, and thus makes the excreta inconspicuous. The totallight transmittance of the top sheet 12 may be appropriately adjusteddepending on a thickness of the top sheet 12, a material forming the topsheet 12, fiber density of a synthetic fiber forming the top sheet 12,etc.

(2) Action and Effect

In the absorbent sheet for pets 10 according to the above-describedembodiments, an odor of water failing to be absorbed into the absorbentcore 20 or an odor of excreta attached to the material such as thenonwoven fabric included in the absorbent sheet for pets 10 may beremoved or turned into a fragrance for a long time by the aroma chemical32 provided on the top sheet 12 side relative to the absorbent core 20.In addition, since the L*value of the colored area 18 is 50 or less, atrace of the wet absorbent core 20, that is, a trace of excreta isconcealed. In addition, concealment of the trace of excreta is improvedby decreasing the total light transmittance of the top sheet 12. In thisway, the user rarely visually recognizes a trace of excreta attached tothe absorbent sheet for pets 10, thereby suppressing an impulse toreplace the absorbent sheet for pets 10. In this way, since the trace ofexcreta is concealed, the user may use the absorbent sheet for pets 10for a long time without causing great discomfort. Further, even thoughthe colored area 18 having a low L*value may give a strong impact onhuman vision, the presence of the colored area 18 may be reduced sincethe top sheet 12 having a low total light transmittance covers thecolored area 18.

According to an embodiment, since the aroma chemical 32 is disposed tobe interposed between the cover layer 40 or 42 and the absorbent core20, a controlled release effect of the aroma chemical 32 may beenhanced.

According to an embodiment, the aroma chemical 32 is included in thecyclodextrin (clathrate). A deodorant or fragrance effect by the aromachemical 32 may be maintained for a long time due to the controlledrelease effect of the aroma chemical of the cyclodextrin. In addition,since the aroma chemical 32 included in the cyclodextrin is released bywater, more aroma chemical 32 is released when excreta is attached tothe absorbent sheet for pets 10. Therefore, the user may recognize thatthe pet has voided excreta by an odor of the aroma chemical 32.

According to an embodiment, the cyclodextrin is solidified by thebinder. A particle size of a bonded particle obtained by bonding thecyclodextrin and the binder together is increased by the binder. In thisway, the bonded particle is less likely to pass through the top sheet 12or the cover layer 40 or 42. Therefore, it is possible to suppress lossof the cyclodextrin and the aroma chemical 32 during manufacture or useof the absorbent sheet for pets 10. In this way, it is possible toimprove cost efficiency at the time of manufacture and maintain thedeodorant or fragrance effect for a long time.

According to an embodiment, the absorbent core 20 has the water-holdingcapacity of 1,000 g/m² or more, preferably 2,000 g/m² or more, and theamount of water seeping from the absorbent core 20 having absorbed 40 mLof water after three minutes is 10 g or less, preferably 5 g or less. Inthis way, it is possible to increase the amount of water absorbed intothe absorbent core 20, and to reduce water failing to be absorbed intothe absorbent core 20 or water seeping from the absorbent core 20 afterbeing absorbed into the absorbent core 20 once as much as possible. Inthis way, it is possible to suppress decay of the absorbent sheet forpets 10 or microbial breeding. In addition, even when a trace of excretais present, a state in which the absorbent sheet for pets 10 is not wetis maintained. For this reason, the absorbent sheet for pets 10 may beused a plurality of number of times without the pet having a dislike. Inaddition, diffusion of excreta in the absorbent core 20 is prevented byincreasing the water-holding capacity of the absorbent core 20. In thisway, even when excreta adheres to the absorbent sheet for pets 10 once,an area in which a trace of the excreta is not attached increases. As aresult, the absorbent sheet for pets 10 may be used a plurality ofnumber of times. Further, when water failing to be absorbed into theabsorbent core 20 or water seeping from the absorbent core 20 afterbeing absorbed into the absorbent core 20 once is reduced as much aspossible, rapid release of the aroma chemical 32 may be suppressed, andthe deodorant or fragrance effect may be exhibited for a long time.

According to an embodiment, the absorbent sheet for pets 10 includes thesuper absorbent polymer 34 provided on the top sheet 12 side relative tothe absorbent core 20. The super absorbent polymer 34 may absorb waterfailing to be retained by the absorbent core 20 or water seeping fromthe absorbent core 20. As a result, even when the absorbent sheet forpets 10 is used for a long time, microbial breeding is prevented, anddecay or an odor of the absorbent sheet for pets 10 may be suppressed.

According to an embodiment, the absorption rate of the absorbentmaterial provided in the absorbent core 20 is higher than the absorptionrate of the super absorbent polymer 34. Excreta may be absorbed into theabsorbent core 20 as much as possible by lowering the absorption rate ofthe super absorbent polymer 34 provided on the top sheet 12 side of theabsorbent core 20. In addition, urine may be rapidly retained, anddiffusion of urine may be suppressed by increasing the absorption rateof the absorbent material provided in the absorbent core 20. In thisway, even when urine adheres to the absorbent sheet for pets 10 once, anarea in which a trace of the urine is not attached increases. As aresult, the absorbent sheet for pets 10 may be used a plurality ofnumber of times. In addition, when diffusion of urine is suppressed, theamount of cyclodextrin not touching urine increases. In this way, thearoma chemical 32 present in an area not touched by urine is maintainedin a state in which the aroma chemical 32 is wrapped with thecyclodextrin for a long time. As a result, the deodorant or fragranceeffect may be maintained for a long time.

According to an embodiment, the antimicrobial and/or the bacteriostat 30provided on the top sheet 12 side relative to the absorbent core 20 isprovided. Even when the absorbent sheet for pets 10 is used for a longtime, the antimicrobial and/or the bacteriostat 30 may suppress decay ofthe excretion part. In particular, since the antimicrobial and/or thebacteriostat 30 is provided on the top sheet 12 side relative to theabsorbent core 20, urine of the pet passes through the antimicrobialand/or the bacteriostat 30 before arriving at the absorbent core 20. Inthis way, the urine of the pet more reliably touches the antimicrobialand/or the bacteriostat 30, and thus an effect of suppressing decay ofexcreta is improved.

According to an embodiment, the powdery antimicrobial and/orbacteriostat 30 attached to the surface of the super absorbent polymer34 is included. Since the antimicrobial and/or the bacteriostat 30 isattached to the surface of the super absorbent polymer 34, theantimicrobial and/or the bacteriostat 30 may be easily and uniformlydispersed on the absorbent core 20 even when the amount of theantimicrobial and/or the bacteriostat 30 is small. Further, when theabsorbent sheet for pets 10 is manufactured, a process of separatelyscattering the super absorbent polymer 34 and the antimicrobial and/orthe bacteriostat 30 is unnecessary, and the antimicrobial and/or thebacteriostat 30 may be scattered simultaneously with the super absorbentpolymer 34. In this way, it is possible to easily manufacture theabsorbent sheet for pets 10 including the super absorbent polymer 34 andthe antimicrobial and/or the bacteriostat 30 on the absorbent core 20.Further, since the antimicrobial and/or the bacteriostat 30 is in thepowder form rather than a liquid form, the antimicrobial and/or thebacteriostat 30 may be inhibited from seeping up to the top sheet 12even when load is applied to the absorbent sheet for pets 10. In thisway, irritation to the pet due to the antimicrobial and/or thebacteriostat 30 may be further reduced.

Although the invention has been described in detail with reference tothe above embodiments, it will be apparent to those skilled in the artthat the invention is not limited to the embodiments described thisspecification. The invention may be implemented as modifications andmodifications without departing from the spirit and scope of theinvention as defined by the scope of the claims. Accordingly, thedescription of the specification is for the purpose of illustration anddoes not have any restrictive meaning to the invention.

Then entire contents of Japanese Patent Applications No. 2014-234940(filed on Nov. 19, 2014) are incorporated in this specification byreference.

Industrial Applicability

According to the invention, it is possible to provide an absorbent sheetfor pets capable of making a trace of excreta of a pet difficult to bevisually recognized.

REFERENCE SIGNS LIST

-   10 . . . absorbent sheet for pets-   12 . . . top sheet-   14 . . . back sheet-   16 . . . core wrap-   18 . . . colored area-   20 . . . absorbent core-   30 . . . antimicrobial and/or bacteriostat-   32 . . . aroma chemical-   34 . . . super absorbent polymer-   40 . . . cover layer-   42 . . . cover layer-   46 . . . pulp material

1. An absorbent sheet for pets comprising: a liquid-permeable top sheet;a liquid-impermeable back sheet; an absorbent core provided between thetop sheet and the back sheet; a colored area covered with the top sheetand visually recognizable from the top sheet side; and an aroma chemicalprovided on the top sheet side relative to the absorbent core, whereinan L*value of the colored area in an L*a*b*color system is 50 or less,and a total light transmittance of the top sheet is in a range of 40 to80%.
 2. The absorbent sheet for pets according to claim 1, furthercomprising a cover layer provided between the top sheet and theabsorbent core, wherein the aroma chemical is provided between the coverlayer and the absorbent core.
 3. The absorbent sheet for pets accordingto claim 1, wherein the aroma chemical is included in cyclodextrin. 4.The absorbent sheet for pets according to claim 3, wherein thecyclodextrin is solidified by a binder.
 5. The absorbent sheet for petsaccording to claim 1, wherein the absorbent core has a water-holdingcapacity of 1,000 g/m2 or more, and an amount of water seeping from theabsorbent core having absorbed 40 mL of water is 10 g or less afterthree minutes.
 6. The absorbent sheet for pets according to claim 1,further comprising a super absorbent polymer provided on the top sheetside relative to the absorbent core.
 7. The absorbent sheet for petsaccording to claim 6, wherein an absorption rate of an absorbentmaterial provided in the absorbent core is higher than an absorptionrate of the super absorbent polymer.
 8. The absorbent sheet for petsaccording to claim 1, further comprising an antimicrobial and/or abacteriostat provided on the top sheet side relative to the absorbentcore.
 9. The absorbent sheet for pets according to claim 6, furthercomprising an antimicrobial and/or a bacteriostat in a powder formattached to a surface of the super absorbent polymer.